Barges are commonly used for conveying cargo over rivers, oceans and other waterways. They are an efficient solution for hauling materials because they can be connected together in sequence for carrying large cargo loads without requiring wide or deep waters. In addition, they can be pulled or pushed by a single tug, which makes them even more efficient. Unfortunately, however, because they are so large and propelled by a single tug, barges are susceptible to destructive collisions with objects such as bridges and piers because of their great momentum and limited maneuverability. In fact, on rivers for example, numerous accidents occur every year with some having disastrous consequences. Thus, it is vitally important that the tug operator (or pilot) continually be in control of the tug/barge combination while it is in motion.
Several solutions have been developed for avoiding accidents caused by negligent or incapacitated operators. For example, there has been developed an automatic collision warning system, as shown in U.S. Pat. No. 3,660,846, which operates in cooperation with a conventional radar system to automatically actuate an alarm system upon the location by the radar system of an object within a predetermined area. This then requires the operator of a ship or the like carrying the collision warning system to make some decision with regard to the located object. If, for example, the object is of no danger to the navigation of the ship, the operator may merely deactivate the alarm; however, if the object is on a collision course, the operator would take some evasive action. Unfortunately, however, this approach has several drawbacks especially with respect to barge tugs. While some tugs have radar systems, they are not typically suited for collision avoidance systems (“CAS”) because of the tug's close proximity to common river structures such as buoys, piers, and the like. Moreover, for radar CAS systems to work well, they generally require straight “lines of sight” to potential obstacles, but rivers typically fail to satisfy this requirement with their bends and contours. In addition, the effectiveness of such an approach relies on the pilot taking appropriate action in response to a collision warning. It assumes that the pilot is viable and in control of the vessel, but if the pilot-is impaired or unconscious, it ceases to be effective. This is a major problem because many if not most barge accidents are caused by the pilot becoming incapacitated (e.g., falling asleep or blacking out from a medical condition).
To redress this problem, other systems monitor the pilot's physical state to ensure that the operator remains conscious and in control of the vehicle. Systems have been used that monitor physical attributes of the operator such as eye movement and posture to verify that the operator is awake and in control. For example, U.S. Pat. No. 6,575,902 to Burton discloses an operator vigilance monitoring system that includes means for gathering movement data associated with the operator. The movement gathering means includes sensors such as touch sensitive mats placed in locations of the vehicle that make contact with the driver, such as on the seat, steering wheel, pedal(s), seat belt or the like. Signals from the various sensors/mats are processed and analyzed by a processor, which is programmed to recognize particular movement signatures or patterns of movement, driver posture or profile and to interpret these to indicate that vigilance has deteriorated or is below an acceptable threshold. This solution may be effective, but it is complex and not convenient for operators such as tug pilots who are typically not confined to a specific position in the wheel house.
Accordingly, what is needed is an improved, efficient system and method for avoiding vehicle accidents that may be caused by an incapacitated or absent operator.